# frozen_string_literal: true

module Utils
  # Helper functions for interacting with tar files.
  #
  # @api private
  module Tar
    module_function

    TAR_FILE_EXTENSIONS = %w[.tar .tb2 .tbz .tbz2 .tgz .tlz .txz .tZ].freeze

    def available?
      executable.present?
    end

    def executable
      return @executable if defined?(@executable)

      gnu_tar_gtar_path = HOMEBREW_PREFIX/"opt/gnu-tar/bin/gtar"
      gnu_tar_gtar = gnu_tar_gtar_path if gnu_tar_gtar_path.executable?
      @executable = which("gtar") || gnu_tar_gtar || which("tar")
    end

    def validate_file(path)
      return unless available?

      path = Pathname.new(path)
      return unless TAR_FILE_EXTENSIONS.include? path.extname
      return if Utils.popen_read(executable, "-tf", path).match?(%r{/.*\.})

      odie "#{path} is not a valid tar file!"
    end

    def clear_executable_cache
      remove_instance_variable(:@executable) if defined?(@executable)
    end
  end
end
